A Robust Stabilization Method of Power Converter for Islanded Microgrids to Realize Plug and Play Function

In this paper, we study a control method that maintains stability regardless of the number of connected power converters in islanded microgrids. It is known that variations in the number of the power converters connected to the islanded microgrids may lead to system instability, since the change of the number of the connected power converters is equivalently considered as variations of the grid impedance. Therefore, we study a control method for the individual power converter that is robust against the grid impedance variations and clarify the stability range, since it is possible to achieve robust stability of the whole microgrid system by configuring it only with the power converters that are robust against the variations of the grid impedance. We present stability analysis, and simulation and experimental verifications of the proposed robust stabilization method.